Hydraulic motor-vehicle brake system with anti-locking control and automatic actuation of the brakes for the control of the drive and/or travel dynamics

ABSTRACT

A hydraulic automotive vehicle brake system with brake slip control and automatic brake management for traction control and/or driving dynamics control includes a braking pressure generator which is hydraulically connectable to at least one wheel brake and a pressure fluid accumulator by way of pressure modulation valves, at least one pump which is connected with its suction side to a pressure fluid accumulator and with its pressure side to a pressure fluid conduit that extends from the braking pressure generator to the wheel brake, the pressure fluid conduit comprising the pressure modulation valves and a pressure sensor that is connected to the pressure fluid conduit in between the braking pressure generator and the pressure modulation valves. The pressure sensor is accommodated in a housing which houses the pressure modulation valves.

BACKGROUND OF THE INVENTION

The present invention relates to a hydraulic automotive vehicle brakesystem with brake slip control and automatic brake management for activebrake operations such as traction control and driving dynamics control.

German patent No. 42 32 311 discloses a hydraulic automotive vehiclebrake system with anti-lock control which, in addition, includesautomatic brake management for driving dynamics control to improve thevehicle tracking behavior. Special provisions must be made for drivingdynamics control or traction slip control in order to have a promptpressure fluid supply for brake management provided by a pump. Amongothers, the provisions include the arrangement of a pressure sensor atthe pressure fluid conduit extending from the braking pressuregenerator, with a view to sensing the pilot pressure that is generatedby the driver in the braking pressure generator.

A design variation relating to the arrangement of the pressure sensor ona special precharging device is shown in the journal ATZ, 96th edition,No. 11, on page 687. Generally, a complicated cable connection to theelectronic control unit is required due to the positioning of thepressure sensor on the housing of the so-called charging piston unit.

Therefore, an object of the present invention is to provide a hydraulicautomotive vehicle brake system with brake slip control and automaticbrake management for traction control and/or driving dynamics control sothat the pressure sensor can be mounted, by relatively reducedstructural efforts, in a way being protected against external influencesand electrically connectable to the electronic control unit in avirtually reliable fashion.

SUMMARY OF THE INVENTION

According to the present invention, this object is achieved for ahydraulic automotive vehicle brake system of the mentioned type by thecharacterizing features of patent claim 1. To reach the objective, thepresent invention is based on the idea of arranging the pressure sensorin a housing which accommodates the pressure modulation valves.

Further features and preferred design variations of the presentinvention can be seen in the subclaims which will be explained in thefollowing, reference to the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings,

FIG. 1 is a cross-sectional view of a pressure sensor.

FIG. 2 is a top view of the housing for the pressure modulation valves.

FIG. 3 is the inside view of a cover for the housing shown in FIG. 2.

DATAILED DESCRIPTION OF THE DRAWINGS

FIG. 1 shows in a view (which is not drawn to scale) a preferredembodiment of a pressure sensor 1 of the claimed invention. The pressuresensor 1, with its stepped housing, is attached by a self-caulkingengagement 11 in a stepped bore 12 of a housing 2 accommodating pressuremodulation valves 3. The section of the housing 2 illustrates a branchline of pressure fluid conduit 13 which provides a connection between abraking pressure generator (not shown) and the pressure modulationvalves 3. Pressure sensor 1 includes a measuring elements chamber whichhouses a preferably capacitive transducer 9. An annular seal 14 isinterposed between the housing of the pressure sensor 1 and thecapacitive transducer 9. Seal 14 prevents the escape of pressure fluidfrom the pressure fluid conduit 13. Remote from the hydraulicallyapplied end face of the transducer 9 is a supporting plate 15 whichtakes up the pressure force applied by the fluid to the transducer 9.Contact pins 16 at the transducer 9 extend through the supporting plate15 until another hollow chamber of the pressure sensor 1 which houseselectric or electronic components 10 of the pressure sensor 1. Theelectronic components 10 of the pressure sensor 1 can also be mounted ona printed circuit board 8. The hollow chamber for the electroniccomponents 10 in the hollow chamber and to a contact 19 which isstationarily arranged in the cover 4. Cover 4 has a carrier plate 7 onwhich electric or electronic components 10 are mounted. In the presentembodiment, the electric component 10 is configured as a printed circuitboard which is soldered to the contact pins of the contacts 19 embeddedin the carrier plate 7. Preferably, the contact pins are laminated witha plastic material in the bores of the carrier plate 7. Contacts 19 arenot attached directly on the carrier plate 7 but are fixed in a plugconnector 5, preferably made as a plastic injection-molded part. Plugconnector 5, being part of the cover 4, is slipped with its bowl-shapedrecess on the plug housing 17 of the pressure sensor 1. To seal thebowl-shaped aperture between the plug housing 17 and plug connector 5,preferably, a profile seal 6 is arranged which, in the presentillustration, is retained as a preassembled part on the neck of the plughousing 17, sealing under the action of the pressing force of the cover4 on the pressure sensor 1. With the exception of the electric orelectronic component parts, 10 and the contacts 19, or the contact pins16, all other above-mentioned elements are rotationally symmetrical asregards their arrangement and construction. As an alternative of thepresent invention as shown in the drawings, the profile seal 6 can beenclosed by the plug connector 5.

FIG. 2 shows a total top view of the valve housing 2, housing in aplurality of parallel rows the pressure modulation valves 3 and thepressure sensor 1 (shown in FIG. 1) in a double design in one plate.Preferably, housing 2 is made of a softer material than the housings ofthe pressure sensor 1 and the pressure modulation valves 3. Therefore,the above mentioned pressure sensors 1 and pressure modulation valves 3can be pressed by self-caulking engagement, in a very simple manufacturein one joint operation, into the housing 2 which is preferably made oflight metal. To this end, housing 2 has a symmetric drilling pattern forthe stepped bores 12. The distance between two valve rows is chosen sothat space for the radial pistons of a pump is left in between therespective valve rows. Further, it can be seen in FIG. 2 that each ofthe pressure sensors 1, arranged on the same axis laterally offset tothe valve rows, has three contact points on the conductor paths 18configured as a printed circuit board.

The plug configuration which interacts with the configuration of theindividual elements shown in FIG. 2 can be taken from FIG. 3. FIG. 3shows the cover 4 which is generally conformed to the block shape of thehousing 2. Cover 4 houses the coils 20 for the pressure modulationvalves 3 and includes for each pressure sensor 1 the plug connector 5known from FIG. 1. In the top view of FIG. 3, in addition, the contacts19 interacting with the contacts of the pressure sensor 1 can be seen inthe plug connector 5. Profile seal 6 known from FIG. 1 has an annularconfiguration in FIG. 2 and is arranged on the plug housing 17. Thus,exclusively the thin-walled webs of the bowl-shaped cover 4 can be seenin FIG. 3. Cover 4 is injection-molded as a frame from a homogeneousplastic part to which also the coils 20 are attached. This provides alargely closed, compact unit of the cover 4 in which all electricalconnections for the pressure sensors 1 and the coils 20, as shown inFIG. 1, are integrated. Especially contact pins and conductor paths areparticularly appropriate as electrical connections in the sense of aprinted circuit board arrangement, and they are preferably cast withplastics in the plug connectors 5 or on the carrier plate 7.

From this results a manufacture in conformity with the demands ofautomation so that the manufacturing process is reduced to a minimum ofoperation steps. Cable assemblies and separate cable connections are notrequired. A largely central plug connection is thereby achieved on thecover 4, due to which all coils 20 and pressure sensors 1 are in contactin a way protected against moisture and short circuits. This achieves avirtual isolation of the hydraulic part of FIG. 2 in relation to theelectric or electronic part of FIG. 3, with the result of separatediagnosis and assembly possibilities. A relatively simple self-centeringof the coils 20, elastically suspended in the cover 4, is achieved byseating the cover 4 on the block-shaped housing 2. The valve domes ofthe pressure modulation valves 3 and the plug housing 17 of the pressuresensors 1 project from the housing. Thus, the plug housings 17 of thepressure sensors 1 are also accommodated in the bowl-shaped cover andare pressed against the contact points of the conductor paths 18,preferably by spring-loaded contacts 19.

FIG. 4 shows a vehicle brake system with brake slip control andautomatic brake management including a braking pressure generator 22which is connected to at least one wheel brake 23 and a pressure fluidaccumulator 24 by way of pressure modulation valves. At least one pump26 is connected with its suction side to the pressure fluid accumulator24 and its pressure side to pressure fluid conduit 13 that extends fromthe braking pressure generator 22 to the housing 2 which contains thepressure modulation valves and the pressure sensor.

We claim:
 1. A hydraulic automotive vehicle brake system with brake slipcontrol and automatic brake management, including a braking pressuregenerator which is hydraulically connectable to at least one wheel brakeand a pressure fluid accumulator by way of pressure modulation valves,at least one pump which is connected with its suction side to thepressure fluid accumulator and with its pressure side to a pressurefluid conduit that extends from the braking pressure generator to thewheel brake, the pressure fluid conduit comprising the pressuremodulation valves and a pressure sensor that is connected to thepressure fluid conduit in between the braking pressure generator and thepressure modulation valves, the pressure sensor being accommodated in ahousing which houses the pressure modulation valves,wherein a cover isattached to the housing and is arranged on the pressure modulationvalves and the pressure sensor, and wherein the cover includes a carrierplate, the carrier plate providing an electrical connection to thepressure sensor.
 2. The brake system as claimed in claim 1,wherein aplug connector is fitted between the cover and the pressure sensor. 3.The brake system as claimed in claim 2,wherein a profile seal isinterposed between the plug connector and the pressure sensor.
 4. Thebrake system as claimed in claim 1,wherein the pressure sensor includesin a sensor housing a capacitive transducer which is connected toelectric and/or electronic components.
 5. The brake system as claimed inclaim 1,wherein the pressure sensor and the pressure modulation valvesare attached in parallel stepped bores of the housing by way of aself-caulking engagement.